Rituximab or azathioprine maintenance in ANCA-associated vasculitis

Something Out of Nothing: A Rare Case of Pulmonary Renal Syndrome With Pauci-Immune Glomerulonephritis and Diffuse Alveolar Hemorrhage With Negative Serologies

Background: Pauci-immune crescentic glomerulonephritis (CrGN) is one of the most common etiologies of rapidly progressive glomerulonephritis. This condition presents with crescentic glomerulonephritis with little or no immunoglobulin staining and negative serological workup aside from a positive antineutrophil cytoplasmic autoantibody (ANCA). Typically, patients with pauci-immune CrGN have an underlying systemic small vessel vasculitis, but in rare cases, it presents without any known vasculitis or ANCA. Pauci-immune ANCA negative CrGN is often strictly isolated to the kidneys. In this case, we present a patient with ANCA negative, pauci-immune CrGN with severe diffuse alveolar hemorrhage.

Case Presentation: A 66-year-old Hispanic woman with a past medical history of controlled hypertension presented with fatigue and dysphagia. On admission, her vital signs were significant for hypoxia on room air, and her physical exam was remarkable for crackles bilaterally. The initial laboratory results revealed anemia (hemoglobin 5.2 g/dL), hyperkalemia (6.3 mmol/L), elevated creatinine (4.50 mg/dL, with a baseline of 0.9mg/dL). Urinalysis showed moderate blood and urine protein (200 mg/dL). Urine microscopic examination showed 25-50 RBCs seen/high power field.

The patient was admitted to ICU due to hypoxia, a computed tomography scan of the chest/abdomen/pelvis was obtained and revealed multifocal pulmonary consolidations. A blood transfusion was ordered. The patient began to have hemoptysis and subsequent bronchoscopy showed diffuse alveolar hemorrhage. ICU team proceeded to intubate her as the hemorrhage continued to worsen. Further workup revealed a positive anti-nuclear antibodies (ANA) of 1:40, but otherwise negative serologies including myeloperoxidase (MPO)-ANCA, glomerular basement membrane antibody, and anti-double stranded DNA. Kidney biopsy showed necrotizing glomerulonephritis with crescents and negative immunofluorescence. She was diagnosed with pauci-immune ANCA-negative vasculitis with associated diffuse alveolar hemorrhage and nephritis based on these results and was started on pulse-dose steroids. The patient was started on intravenous (IV) high-dose cyclophosphamide, which helped improved the overall clinical condition significantly. After creatinine began trending down and urine output improved, the patient was discharged on a regimen of daily oral cyclophosphamide and steroid taper. Patient oxygen requirements decreased and she was sent home with supplemental oxygen while requiring 3L/min of oxygen.

Conclusion: Pauci-immune and ANCA-negative glomerulonephritis with concurrent diffuse alveolar hemorrhage is exceptionally rare. In this situation, medical management relied on clinical evidence from similar populations in the use of steroids and cyclophosphamide. This case report aims to shed more light on the clinical progression and management of this condition. Here we present a case of pulmonary-renal syndrome with biopsy-proven glomerulonephritis but without ANCA positive serologies.

Slo-Mo anti-neutrophil cytoplasmic antibody-associated renal vasculitis

Nephrologists are familiar with severe cases of anti-neutrophil cytoplasmic antibodies-associated vasculitis (AAV) presenting as rapidly progressive glomerulonephritis. However, less is known about AAV with slowly progressive renal involvement. While its existence is acknowledged in textbooks, much remains unknown regarding its relative frequency versus more aggressive cases as well as about the optimal therapeutic approach and response to therapy. Moreover, this uncommon presentation may be underdiagnosed, given the scarce familiarity of physicians. In this issue of Clinical Kidney Journal, Trivioli et al. report the largest series to date and first systematic assessment of patients with AAV and slowly progressive renal involvement, defined as a reduction in estimated glomerular filtration rate (eGFR) of 25-50% in the 6 months prior to diagnosis after excluding secondary causes. Key findings are that slowly progressive AAV may be less common than previously thought, although it still represents the second most common presentation of renal AAV, it usually has a microscopic polyangiitis, anti-myeloperoxidase, mainly renal phenotype in elderly individuals, diagnosis may be late (over one-third of patients had end-stage kidney disease at diagnosis), clearly identifying an unmet need for physician awareness about this presentation, but those not needing renal replacement therapy at diagnosis still responded to immunosuppression.

Rituximab for auto-immune alveolar proteinosis, a real life cohort study

Background

Whole lung lavage is the current standard therapy for pulmonary alveolar proteinosis (PAP) that is characterized by the alveolar accumulation of surfactant. Rituximab showed promising results in auto-immune PAP (aPAP) related to anti-GM-CSF antibody.

Methods

We aimed to assess efficacy of rituximab in aPAP in real life and all patients with aPAP in France that received rituximab were retrospectively analyzed.

Results

Thirteen patients were included. No patients showed improvement 6 months after treatment, but, 4 patients (30%) presented a significant decrease of alveolar-arterial difference in oxygen after 1 year. One patient received lung transplantation and one patient was lost of follow-up within one year. Although a spontaneous improvement cannot be excluded in these 4 patients, improvement was more frequent in patients naïve to prior specific therapy and with higher level of anti-GM-CSF antibodies evaluated by ELISA. No serious adverse event was evidenced.

Conclusions

These data do not support rituximab as a second line therapy for patients with refractory aPAP.

B cell repopulation kinetics after rituximab treatment in ANCA-associated vasculitides compared to rheumatoid arthritis, and connective tissue diseases: a longitudinal observational study on 120 patients

Background

B cell depletion with rituximab (RTX) is approved for treatment of rheumatoid arthritis (RA) and ANCA-associated vasculitides (AAV). Recently, RTX has been shown to be effective in AAV maintenance therapy, but an optimal RTX treatment schedule is unknown and the time to B cell repopulation after RTX has not been studied.

Methods

Retrospective single-center analysis of B cell repopulation in patients with AAV, RA or connective tissue disease (CTD) treated with RTX.

Results

Beginning B cell repopulation within the first year after RTX treatment was observed in 93% of RA and 88% of CTD patients. Only 10% of patients with granulomatosis with polyangiitis (GPA) and microscopic polyangiitis (MPA) and no patient with eosinophilic granulomatosis with polyangiitis (EGPA) showed B cell repopulation within this time. Median time of B cell depletion was 26 months in GPA/MPA, and 21 months in EGPA compared to 9 months in RA, and 8 months in CTD (p < 0.0001). In 25 AAV-patients B cell depletion lasted for at least 44 months. There was a significant decline in serum immunoglobulin concentrations in GPA/MPA patients, but not in patients with RA or CTD. Significantly more GPA/MPA patients developed hygogammaglobulinemia (IgG <7 g/L) compared to patients with RA or CTD.

Conclusions

In contrast to RA and CTD, in AAV RTX induces long-lasting depletion of B cells that is associated with decreased antibody production. This observation points toward potential defects in the B cell compartment in AAV that are unmasked by immunosuppressive treatment and has important implications for the design of maintenance treatment schedules using RTX.

Patients with ANCA-associated vasculitis admitted to the intensive care unit with acute vasculitis manifestations: a retrospective and comparative multicentric study

PURPOSE

Data for ANCA-associated vasculitis (AAV) patients requiring intensive care are scarce.

METHODS

We included 97 consecutive patients with acute AAV manifestations (new onset or relapsing disease), admitted to 18 intensive care units (ICUs) over a 10-year period (2002-2012). A group of 95 consecutive AAV patients with new onset or relapsing disease, admitted to two nephrology departments with acute vasculitis manifestations, constituted the control group.

RESULTS

In the ICU group, patients predominantly showed granulomatosis with polyangiitis and proteinase-3 ANCAs. Compared with the non-ICU group, the ICU group showed comparable Birmingham vasculitis activity score and a higher frequency of heart, central nervous system and lungs involvements. Respiratory assistance, renal replacement therapy and vasopressors were required in 68.0, 56.7 and 26.8% of ICU patients, respectively. All but one patient (99%) received glucocorticoids, 85.6% received cyclophosphamide, and 49.5% had plasma exchanges as remission induction regimens. Fifteen (15.5%) patients died during the ICU stay. The following were significantly associated with ICU mortality in the univariate analysis: the need for respiratory assistance, the use of vasopressors, the occurrence of at least one infection event in ICU, cyclophosphamide treatment, sequential organ failure assessment at admission and simplified acute physiology score II. After adjustment on sequential organ failure assessment or infection, cyclophosphamide was no longer a risk factor for mortality. Despite a higher initial mortality rate of ICU patients within the first hospital stay (p < 0.0001), the long-term mortality of hospital survivors did not differ between ICU and non-ICU groups (18.6 and 20.4%, respectively, p = 0.36). Moreover, we observed no renal survival difference between groups after a 1-year follow-up (82.1 and 80.5%, p = 0.94).

CONCLUSION

This study supports the idea that experiencing an ICU challenge does not impact the long-term prognosis of AAV patients.

Therapeutic advances in the treatment of vasculitis

Considerable therapeutic advances for the treatment of vasculitis of the young have been made in the past 10 years, including the development of outcome measures that facilitate clinical trial design. Notably, these include: a recognition that some patients with Kawasaki Disease require corticosteroids as primary treatment combined with IVIG; implementation of rare disease trial design for polyarteritis nodosa to deliver the first randomised controlled trial for children; first clinical trials involving children for anti-neutrophil cytoplasmic antibody (ANCA) vasculitis; and identification of monogenic forms of vasculitis that provide an understanding of pathogenesis, thus facilitating more targeted treatment. Robust randomised controlled trials for Henoch Schönlein Purpura nephritis and Takayasu arteritis are needed; there is also an over-arching need for trials examining new agents that facilitate corticosteroid sparing, of particular importance in the paediatric population since glucocorticoid toxicity is a major concern.

Place in therapy of rituximab in the treatment of granulomatosis with polyangiitis and microscopic polyangiitis

Granulomatosis with polyangiitis and microscopic polyangiitis are small vessel vasculitides characterized by circulating antineutrophil circulating antibodies. Standard treatment for active severe disease has consisted of cyclophosphamide with glucocorticoids with or without plasmapheresis, which achieves approximately 75% sustained remission, but carries significant adverse effects such as malignancy, infertility, leukopenia, and infections. The role of B cells in the pathogenesis of anti-neutrophil circulating antibodies-associated vasculitis has been established, and as such, rituximab, a monoclonal anti-CD20 antibody, has been studied in treatment of active granulomatosis with polyangiitis and microscopic polyangiitis (induction) and in maintaining remission. Rituximab has been shown to be effective in inducing remission in several retrospective studies in patients with refractory disease or cyclophosphamide intolerance. The RAVE and RITUXVAS trials demonstrated rituximab is a noninferior alternative to standard cyclophosphamide-based therapy; however, its role in elderly patients and patients with severe renal disease warrants further investigation. Rituximab has been compared with azathioprine for maintaining remission in the MAINRITSAN trial and may be more efficacious in maintaining remission in patients treated with cyclophosphamide induction. Rituximab is not without risks and carries a similar adverse event risk rate as cyclophosphamide in randomized control trials. However, its use can be considered over cyclophosphamide in patients who have relapsing or refractory disease or in young patients seeking to preserve fertility.